*{
    padding: 0;
    margin: 0;
}
ul{
    width: 200px;
    height: 200px;
    margin:100px auto;
    position: relative;
    transform-style: preserve-3d;
    perspective: 500px;
}
ul li{
    list-style: none;
    width: 200px;
    line-height: 200px;
    text-align: center;
}
ul li:nth-child(1){
    background: red;
    position: absolute;
    transform: rotateY(0deg);
    transition: transform 1s linear;
}
ul li:nth-child(2){
    background: salmon;
    position: absolute;
    transform: rotateY(180deg);
    transition: transform 1s linear;
}

ul:hover .wn{
    transform: rotateY(180deg);
}

ul:hover .wn1{
    transform: rotateY(360deg);
}